The present invention relates to access networks.
Traditionally a user has accessed an Internet service provider (ISP) using a circuit switched access network for example the public switch telephone network (PSTN). In this arrangement the user can select an ISP of choice by dialling the appropriate telephone number; a dedicated physical circuit is then set up via the phone lines and central office switching equipment between the users modem and the ISP.
Recently alternative access networks have become available in which packet switching is used. In a packet switched access network, data to be sent or received is broken down into packets, each of which includes the destination address and the packet sequence. The packets are then transmitted over the network taking any number of routes to reach their destination. At the destination the packets are received and the data retrieved by assembling the packet data in its proper sequence. While packets can take different routes to reach their final destination, a virtual circuit as opposed to a switched circuit, is said to have been formed across the access network between sender and receiver. Examples of packet switched access network enabling technology includes asymmetric digital subscriber line (ADSL), cable modem, the third generation mobile system known as Universal Mobile Telecommunication System (UMTS), as well as various fixed wireless data networks technology.
Many packet switched access networks are connected to other networks such as the Internet for example by a single connection facility, for example an ISP. It has not been possible for a user to select one facility or ISP over another in packet switched access networks, as has been possible with traditional circuit switched access networks.
It is an object of the present invention to provide a method of selecting in a packet switched access network an interface to another network.
It is a further object of the present invention to provide a method of selecting in a packet switched access network an ISP to the Internet. In a first aspect the present invention provides a method for a user in a packet switched access network to select a connection facility to a second network, the method comprising:
the user prepending the access network address of said connection to each data packet sent onto the access network by said user;
the access network connection removing said prepended address from each said packet prior to sending said packets onto said second network.
Preferably said second network is the Internet, said access network connection is an Internet Service Provider (ISP), and said data packets are IP packets.
Preferably said access network and said second network use the same data packet header format.
In a second aspect the present invention provides a method of transmitting packets across an access network from a user to a connection facility to a second network, the method comprising:
accepting from said user of said access network data packets prepended with the access network address of said connection facility; and
forwarding said packets to said connection facility.
Preferably said second network is the Internet, said connection facility is an Internet Service Provider (ISP), and said data packets are IP packets.
Preferably said access network and said second network use the same data packet header format.
In a third aspect the present invention provides a method of transmitting packets across an access network from a connection facility to a second network to a user of said access network, the method comprising:
accepting from said facility data packets prepended with the access network address of said user; and
forwarding said packets to said user.
In a fourth aspect the present invention provides a signal comprising an access network data packet for transporting between a user of said network and a destination in a second network to which said access network is connected, said packet comprising an access network address corresponding to a connection facility between said networks.
In a further aspect the present invention provides access network equipment comprising:
means for accepting from a user of said access network data packets prepended with the access network address of a connection facility between said access network and a second network; and
means for forwarding said packets to said connection facility.
In a still further aspect the present invention provides access network equipment comprising:
means for accepting from a connection facility between said access network and a second network data packets prepended with the access network address of a user of said access network; and
means for forwarding said packets to said user.
In a yet further aspect the present invention provides connection facility equipment for connecting an access network with a second network, the equipment comprising:
means for accepting data packets from said access network having the access network address of said connection;
means for removing said address and forwarding said packets onto said second network.
In another aspect the present invention provides connection facility equipment for connecting an access network with a second network, the equipment comprising:
means for accepting data packets from said second network;
means for prepending the address of an access network user to said packet and forwarding said packets onto said access network.